The important organelles protein(mitochondria and microsome),cytochromes P450 of drug-metabolizing enzymes as well as aspartate transaminase(AST)and alanine transaminase(ALT) in serum of important liver functional indices were comparatively analyzed by Lowry protein measure,CO difference spectrum and colorimetric method to explore the difference of liver functional indices between largemouth bass and mice from different evolution status.Results showed that the level of mitochondria protein,cytochromes P450 as well as ALT in largemouth bass liver were significantly lower compared to mice.The level of microsome protein and AST in largemouth bass and mice liver were not significantly different.These data suggest that liver functional indices of largemouth bass and mice from different evolution status are significantly different,the functions of liver are closely correlated with the content of cytochromes P450 as well as ALT in liver.